INVESTIGADORES
RUIZ Lucas Ernesto
congresos y reuniones científicas
Título:
RECONSTRUCTIONG AND ANALYZING THE FLUCTUATIONS OF GLACIER ESPERANZA NORTE, WET ANDES, ARGENTINA, SINCE THE LITTLE ICE AGE
Autor/es:
RUIZ, L.; MASIOKAS, M.; VILLALBA, RICARDO.
Lugar:
Valdivia
Reunión:
Simposio; II International Symposium "Reconstructing Climate Variations in South America and the Antartic Peninsula over the last 2000 years"; 2010
Institución organizadora:
CECS
Resumen:
Glacier Esperanza Norte (also known as Glacier Túnel,
42°15′S, 72°10′W) is one of the largest glaciers in the north Patagonian Andes
of Argentina and one of the very few glaciers with information about frontal
fluctuations for the last centuries. This valley glacier is part of the
Esperanza/Universo icefield and had in 2007 an area of 10.5 km2, a mean
altitude of 1844 m, and a length of 4.94 km. The glacier is formed in a
compound basin and has a land terminating, clean ice tongue. The longitudinal
profile of the glacier is characterized by a relatively flat accumulation area
and a steep ice fall in which the ablation area is currently located. Although
basic data for this glacier has been included in the World Glacier Inventory,
this information is presently inadequate for reconstructing the Equilibrium
Line Altitude (ELA), length or areal variations. Here we present a
reconstruction of glacier geometry and mass balance/glacier flux response for
the past 400 years using an inverse glaciological approach based on
dendrocronology data, historic photos, satellite images and a new geomorphology
map made from field work and remote sensing data. Preliminary results indicate
that the Little Ice Age maximum extent occurred in the early 17th century and
has been followed by at least 20 glacier readvances or standstills embedded
within an overall retreating. An analysis of the glaciers response to changes
in mass balance/glacier flux is performed in order to explain changes in the
glaciers geometry and the characteristics of the frontal moraines. This
hypothesis is further explored with different ELA reconstruction methods in combination
with climate reconstructions from other proxies.